HIV-positive cigarette smokers may face a higher risk of cardiovascular disease, chronic obstructive pulmonary disease and various cancers, but they may also have a lower risk of Kaposi’s sarcoma (KS), according to a letter published by National Cancer Institute (NCI) researchers in the January 14 issue of AIDS.

KS is a cancer that predominantly causes skin lesions but can also spread to other parts of the body, including the lymph nodes. Primarily caused by a member of the herpes virus family, KS strikes people with HIV most commonly when their CD4 counts fall below 200.

To investigate hints from a couple of small studies that smoking may actually protect people from developing KS, James Goedert, MD, from the NCI in Rockville, Maryland, and his colleagues conducted a study of all people diagnosed with KS on the Italian island of Sicily between 2002 and 2006. He reports the study’s conclusion, without details, in his AIDS letter urging researchers to explore cofactors associated with increased or decreased risks of developing KS.  

Goedert’s team found that people who had ever smoked at least one cigarette per week were three times less likely to develop KS than people who had never smoked. People who currently smoked were five times less likely to develop KS. The authors acknowledge that the type of study they conducted can’t prove that smoking reduces the risk of KS, and they are not encouraging people to take up or continue smoking. They are hoping, however, that their findings may help identify new ways to reduce the severity of KS disease progression in people with HIV.